Maech 11, 1898,] 



SCIENCE. 



335 



peripheral structure ofBai-rettia strongly re- 

 calls that of some of the parasitic balani. 



The year-book for 1896 of the Museum 

 at Bergen, Norway, where so much excel- 

 lent zoological work has been done in past 

 years, by Daniellsen, Nansen and others, 

 has recently been distributed. The leading 

 paper in this volume * is an investigation 

 of the eyes of Pecten and lAma by K. E. 

 Schreiner. Anyone who has ever examined 

 a living scallop has been struck by the 

 jewel-like beauty of the brilliantly colored 

 eyes on the edge of the mantle. These are 

 shown by Schreiner to possess a rather high 

 type of organization, the details of which 

 are carefully worked out and fully illus- 

 trated. A considerable number of species 

 was examined. On the other hand, the al- 

 lied genus Lima, represented by the gigan- 

 tic deep-water L. excavata, has a very low 

 type of visual organ, a mere open pit lined 

 with pigmented epithelium, much like the 

 analogous organs in Patella. In the same 

 volume f James A. Grieg contributes an 

 article on the Vestland mollusks, including 

 several nudibranchs new to the region. 

 Anatomical details in regard to a variety of 

 Tritonia j^leheia are recorded. Felix Bernard 

 has continued the excellent researches on 

 the development of the hinge-teeth in 

 bivalves, to which we have already called 

 attention in an earlier number of this 

 Journal. In a recent number of the Journal 

 de Conchyliologie % he considers a small group 

 of small bivalves for which is proposed the 

 name Condylocardia, and with which he 

 would unite the genera Carditella and Cardi- 

 topsis in a special family Condylocardiidse. 

 These shells he considers to represent a 

 precocious stage of development of the 

 Carditidte, Astartidse and Crassatellitidaj. 

 They have an internal resilium, and a 



* Bergen's Museums Aarbog for 1896, pp. 1-51, PI. 

 I.-IV., 1897. 



fOp. cit., Art. X., pp. 32., with one plate. 

 ' t No. 3, pp. 169-206, 1897, with one plate. 



striking feature is the near approach to 

 symmetry of the early teeth with respect 

 to the resilium. These small shells are 

 also remarkable in the evidence they aiford 

 of the acceleration and retardation of cer- 

 tain characters relative to the time of ap- 

 pearance of such characters in allied groups. 

 Another paper of more than ordinary in- 

 terest * is on the Anatomy of Chlamydo- 

 concha oreutti, a remarkable Californian 

 bivalve, in which the valves are wholly in- 

 ternal and the adductor muscles so reduced 

 that no trace of them remains. The work 

 of M. Bernard in the main confirms the 

 synopsis of characters given by the writer 

 in 1884, exception being made of the an- 

 terior orifice of the mantle which proves to 

 open into a cid de sac and may represent 

 the point where the final immersion of the 

 valves came to completion. A multitude 

 of details are added to our knowledge of 

 the animal and illustrated in the excellent 

 manner usual with this author. The con- 

 clusion is that this mollusk represents the 

 last term in a developmental series, of 

 which Galeomma represents an early stage. 



In a third paperj" M. Bernai'd describes 

 some interesting new forms, minute bivalves 

 from New Zealand, belonging to the new 

 genera Pachykellya, Cyamiomactra and Perri- 

 erina, with others belonging to Neolepton. 

 All these are distinguished by marked pe- 

 culiarities of the armature of the hinge, 

 which are worked out with extreme care. 

 These papers lead us to anticipate with 

 the greatest interest the general work on the " 

 hinges of bivalves which M. Bernard has 

 announced as in preparation. 



Some years ago Carpenter described a 

 curious little shell from Cape St. Lucas, 

 which he named Philobrya, which appeared 

 to be related to the pearl oysters. After- 



«Ann. Sci. Nat. Zool. Ser. VIII., Vol. IV., pp. 

 321-252, PI. 1, 1897. 



t Extr. Bull. Mus. d'Hist. Nat. Paris, No. 7, pp. 

 309-314, 1897. 



